Fig. 3: Emission indices of volatile particles and non-volatile particles.
From: Fuel sulfur content can modulate contrail ice crystal numbers
Number of volatile particles >5 nm (circles) and non-volatile particles >14 nm (diamonds) per kg fuel burned measured at 9465–9730 m altitude. Measurements were performed in the near field in the 0.5–2 s old exhaust in non-contrail-forming conditions 2 K above TSA and RHi below 60% (a), and in the far field in contrail-forming conditions in the 50–300 s old contrail at air temperatures 9–10 K below TSA and RHi of 70–100% (b). The figure shows median values and 25th–75th percentiles of the emission index for the ultra-low-sulfur HEFA-SPK (green), the low-sulfur Jet A-1 (dark gray), and the medium-sulfur blend fuel (blue); gray dots represent data from single exhaust crossings.
